Near electrical resonance signal enhancement (NERSE) in eddy-current crack detection

摘要: An investigation was performed into the effects of operating an absolute eddy-current testing (ECT) probe at frequencies close to its electrical resonance. A previously undocumented defect signal enhancement phenomenon, resulting from associated shifts in resonant frequency, observed and characterized. Experimental validation on three notch defects a typical aerospace superalloy, Titanium 6Al–4V. conventional ECT operated by sweeping through frequency range about resonance system (1 � 5 MHz). The phenomenon results signal-to-noise ratio (SNR) peak enhancements factor up 3.7, approaching resonance, compared those measured 1 MHz. peaks are shown be result due presence within material. simple, operational approach for raising sensitivity industrial eddycurrent is proposed, based principles near (NERSE) phenomenon. simple procedural change NERSE band does not require complex design, data analysis or, necessarily, identical coils. Therefore, it valuable technique improving sensitivity, which complements other methods. & 2014 Authors. Published Elsevier Ltd. This open access article under CC BY license